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Which Unpatched Holes Most Appeal to Attackers?

There are few better ways to guarantee a system will be breached, compromised and exploited than failing to keep up with vendors' patches. Yet millions of public-facing systems run unpatched.

In an effort to document which previously reported security vulnerabilities are most popular with attackers, government public computer security awareness agencies from five countries on Wednesday released a Top 30 list of targeted high-risk vulnerabilities.

"This Alert provides information on the 30 most commonly exploited vulnerabilities used in these attacks, along with prevention and mitigation recommendations," read an alert from the U.S. Department of Homeland Security's National Cybersecurity and Communications Integration Center and the U.S. Computer Emergency Readiness Team.

An analysis by the Canadian Cyber Incident Response Centre provides the foundation for the list, which was jointly developed by government computer security organizations in Australia, Canada, New Zealand, the United Kingdom and the United States.

The vulnerabilities are not listed by severity. Instead, they are grouped by the vendor or project whose software is affected. Microsoft accounts for 16 of the vulnerabilities, Adobe for 11, Oracle for 2 and OpenSSL for 1.

What's both interesting and depressing about the list is how old some of the vulnerabilities are. For example, in the Microsoft list, some of the 30 most commonly exploited vulnerabilities date to 2009 and 2008, as well as an Internet Explorer malware issue, which first emerged almost nine years ago.

On Microsoft platforms, the attackers' favorite flaws come from the following bulletins:

  • MS08-042
  • MS09-067
  • MS09-072
  • MS10-018
  • MS10-087
  • MS11-021
  • MS12-027
  • MS12-060
  • MS13-008
  • MS13-022
  • MS13-038
  • MS14-012
  • MS14-017
  • MS14-021
  • MS14-060

The malware issue with Internet Explorer is CVE-2006-3227.

The U.S. version of the Top 30 bulletin is available here.

Posted by Scott Bekker on April 29, 2015


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